1. Field
The disclosure relates to a method, system, and article of manufacture for accessing snapshots of a time based file system.
2. Background
In certain situations, it is useful to take “snapshot” copies of a file system at a plurality of points in time and subsequently restore the file system to a previously existing state after the file system has been altered. A snapshot copy may include all files that were present in the file system at the time the snapshot copy was taken. Therefore, a snapshot copy represents the state of the file system at the time the snapshot copy is taken.
The snapshot granularity, i.e., the temporal frequency with which the snapshot copies are taken, may be fixed and may be determined a priori. Commands for performing snapshot copies may be explicitly triggered or scheduled. Certain systems copy existing data to a new area on a disk before writing new data in the same place where the old data resided. This type of “copy-on-write” may impact performance of systems that store snapshot copies.